Calculating land costs - who understands that?

A very layman question: how can I tell if everything is building land? The price is quite high and it won’t work with new construction under a million.

It should actually also be designated as "Gartenland" in the development plan.

Otherwise:

If you have a scaled plan --> 0.4 (floor area ratio) x 975 sqm = 390 sqm. If the building area on the plan is exactly this size, it is all building land.

It should actually also be designated as "Gartenland" in the development plan.

Otherwise:

If you have a to-scale plan -- > 0.4 (floor area ratio) x 975 sqm = 390 sqm. If the building area on the plan is just as big, then it is all building land.

Yep, I don't see it either.
Besides, it would be fatal: Gartenland is not counted as part of the property, so it must be properly designated for the area calculation.
It is and remains a building plot!